Tuesday, May 13, 2014

Part II of Natural Springs, Brownback Salamanders, and the Good Folks of St. Clair County

“Does anybody here in their wildest imagination think that the White Oak Runner becomes a different species when it crosses the Chattahoochee River?”

–Bob Mount, at the 2011 3rd nongame Alabama wildlife conference, in reference to a recent taxonomic revision of ratsnakes.

No sooner did the description of the Brownback Salamander appear did doubt arise as to its validity. Francis Rose thought that, “much of the efforts to discredit the species designation was based in rational ignorance, and that had any one of the detractors viewed the paratypes [the specimens used to describe it as a species], it would be obvious that they were wrong.” Most of the skepticism came from two herpetologists from Auburn University—Bob Mount and George Folkerts—who came to dominate Alabama herpetology during the 1970s through the 1980s, and who had certainly seen the salamanders but were still unconvinced. They would have a disproportionate influence on the salamander’s status, and as we shall soon see, on the student who would eventually conduct the most detailed study on the salamander to date.

Folkerts fired first, with a paper that was perhaps as influential as it was brief. An abstract appeared in the journal Herpetological Review in 1971, in which he hypothesized that the diversity of shapes, sizes, proportions, and color of certain stream salamanders could be explained simply by variation within the same species. Folkerts thought Brownback Salamanders were just local variants of the more widespread Two-lined Salamander, and not a real species. The key prediction of Folkerts’ argument is that each population of spring-dwelling Brownback Salamanders should be more closely related to nearby Two-lined Salamanders than to each other, a prediction that my group would come along and test later.

Based largely on Folkert’s short contribution and Mount’s observations that salamanders “intermediate” between Two-lined Salamanders and Brownback Salamanders could be found at nearly every location where the Brownback Salamander was known, Mount did not treat Eurycea aquatica as a separate species in his landmark state herpetology The Reptiles and Amphibians of Alabama. This was the beginning of a temporary end for our salamander.

Mount’s opinions about species carried considerable authority. His scientific training was during the height of Ernst Mayr’s biological species concept, a concept so influential it is still taught in introductory biology classes. It was a time when the genetic structure of DNA had only just become known. Even modern herpetologists can sympathize; it can be exhausting to keep up with the constant nomenclature changes, rearrangements, and updates.

Mount is a devout defender of his positions to this day, and sometimes declares them quite gruffly at conferences. He despises geneticists and what they’ve done to the old taxonomy. Once at Auburn he looked over my shoulder at a paper I was working on and asked me what in the devil a “Pantherophis” was, which is the current generic name for North American ratsnakes. I told him it was a White Oak Runner (the terrifically old-school common name for the Grey Ratsnake), and jokingly suggested that it was perhaps time he took a herpetology class.

Tom Jones arrived at Auburn right after publication of Bob Mount’s book and became interested in the variation of Eurycea salamanders described in its pages, including the Brownback Salamander “problem,” as well as some tantalizing new forms that were discovered north of Birmingham near a cave in Morgan County. These “Cole Springs ecotypes,” as Mount referred to them, also have the big head, but can come in striking oranges and reddish browns. Was this yet another undescribed Eurycea? Jones decided to try to sort out all these weird forms as a topic for his Master’s thesis. Like many rookie graduate students, he recalls today that, “I had bitten off far more than I could possibly chew.”

The spring near Ebenezer Church, Shelby Co., AL

He began exploring the Appalachian Plateau of northern Alabama, where he collected unusual salamanders near Cole Spring Cave, and travelled to the wilds of Jackson County in northeastern most Alabama where, as he remembers, “I drove up long gravel roads that ended in tar-paper shacks and suspicious looks.” He would spend freezing cold nights camping in his car in the parking lot of churches, which were then considered relatively safe. The grounds of Ebenezer Church in Shelby County contained a spring that would be one of his most productive collection sites, not the least because it was in the neighborhood of two Auburn alumni who let him crash at their house and share a bottle of wine.

Finding the salamanders would prove maddening, something I would also experience many years later. Larval Brownback Salamanders can easily be found at almost any site, which was perfectly fine for our much later genetic analysis. But Tom was comparing the body shapes of adult salamanders, and finding larvae would not cut it. His field notes became peppered with statements like, “where are they?” and, “where the [heck] are the adults?” He spent the better part of a year looking for adult Brownback Salamanders, including at the type locality, with no luck.

Tom Jones today; he is currentlyan Arizona Department of Fishand Game biologist.

On 19 January 1979 he arrived at Ebenezer Church in Shelby County, Alabama in a cold rain. He followed a short trail to the spring run, which was covered with a carpet of the edible, aquatic plant watercress (Nasturtium officinale) so thick that he couldn’t see the water. He started digging with high anticipation through the plants with a dipnet. At the very end of the spring run a large adult male wriggled in. Tom was thrilled: it looked just like it was supposed to look like, in exactly the right habitat, and it was indeed aquatic.

From there the situation would become much more confusing. At some sites he would collect salamanders consistent with Rose and Bush’s description, but these would almost diabolically change color overnight into yellowish salamanders without the characteristic dark sides of the Brownback Salamander. He began finding that the Brownback Salamander could be found along the water’s edge and under rocks near streams, so they were not quite as aquatic as Rose and Bush thought. Some typical limestone springs were occupied by big-headed “aquatica types,” while others, just south of the Coosa River, were occupied by skinny little Southern Two-lined Salamanders with long cirri. One spring in particular actually seemed to have both types.

Tom Jones fist visited Sander’s Spring in St. Clair County on 20 April 1979. The spring gurgles out just downhill from the road running down the Shoal Creek Valley; a neat two-story white house stood adjacent to the several holding ponds of diverted spring water and a small spring house. Here the ridges bend east-west, so to the south was the long, newly-green ridge of the Shoal Creek Mountains, and to the north, the Beaver Creek Mountains. Shoal Creek meandered at the south edge of the property. Margaret Sanders met him at the door and allowed him full access to the property, which he began searching right away. Tom turned small stones looking for salamanders but soon had company: The Sander’s 11 year old son, Albert. After asking Tom what he was up to, Al volunteered to help. At one point Tom turned a large rock and underneath were three salamanders. Tom needed them all, but he only had two hands. Quickly, and without thinking, he popped one of the salamanders in his mouth for temporary storage, and began reaching for the other two. He looked up to find a look of sheer horror on the wide-eyed face of Al Sanders, who then bolted up the hill toward the house hollering for his mama.

Sander’s Spring proved to be a good site for Tom Jones’ research, and he returned year after year, even after his thesis was completed, still trying to wrap his head around what was going on. He enjoyed the beauty of the Shoal Creek Valley and privately thought to himself that it would be the kind of place where he’d like to settle down himself. The family was exceptionally accommodating, and he had good success finding Brownback Salamanders there. He found several nests, including one attended by a male and female. And here he found salamanders that were obviously assignable to both Eurycea aquatica and E. cirrigera, one of only a couple of such sites known where both species occurred.

Jones’ thesis is an exceptional piece of natural history, and included the first large scale attempt to compare the physical features of the Brownback Salamander to its nearby relative, the Southern Two-lined Salamander. However, as Jones would realize soon after he left Auburn, his training under Mount and Folkerts did not lend itself to an objective approach. Reading the thesis you get the impression he was sure there was something special about the salamanders, but he just didn’t have the right analysis to prove it. So he held back from considering the salamander a unique species and left open the possibility that they were some kind of local variant. He reflects now that, “he did the best he could have done under the influence of Mount,” and that it was a “real lesson to me on how professors can influence their students without their even knowing it.”

When I pressed him for an example of how Mount influenced him, he offered a telling anecdote. During his thesis proposal meeting, one of his committee members asked how he intended to randomize his sampling. In other words, how would he reduce bias in his study. According to Jones, Mount became “unglued.” Before Tom could even open his mouth, Mount barked: “Randomize?! [Heck], you don’t just find these things in a [dad-gun] cotton field!” I don’t want to give the impression that Jones regretted his experience at Auburn. Nothing could be further from the truth. And I should mention too that I greatly respect Mount and Folkerts, especially their focus on natural history. It’s just that the field moved.

Jones’ thesis was used by both detractors and supporters of the salamander’s validity. Meanwhile, Rose stood back and watched from the sidelines, and says that while he was certain that the species was valid, “there was nothing that I could do if the species was relegated to the taxonomic graveyard.” The Brownback Salamander was illustrated and appeared in the 1991 edition of Conant and Collin’s Field Guide to Eastern and Central Amphibians and Reptiles, perhaps its greatest endorsement. But a few years later the salamander was dealt a deathblow—it was not treated separately in James Petranka’s 1998 Salamanders of the United States and Canada.

To make matters worse, it seemed as though nobody could even find the salamander anymore. In a species account about the Brownback Salamander, Francis Rose raised a most alarming prospect: he warned that unscrupulous collectors had apparently wiped out the type population at Glenn Spring. Perhaps this salamander would disappear before its status as a separate species could ever be resolved.

But a small glimmer of hope for the species remained. Using decades-old tissue collected from the type locality, in 2006 Ken Kozak published a genetic analysis of the entire Eurycea bislineata complex and showed that, at least from the type locality, the Brownback Salamander was indeed unique. But the level of sampling in this paper still left open the rather unsavory prospect that the salamanders collected years ago at Glenn Spring were closely related to local populations of Two-lined Salamanders. The specter of ecotypic selection remained. The definitive analysis was still left wide open for anybody who was interested—providing, of course, that anybody could still find them.